ADLINK Technology HDV62, User Manual

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60 Function Library
4.5.4 Callback
Purpose
These functions set or get event handle. Event and callback are
the methods to know when to get frame or to check DI’s state.
Usually applications use only one of them, but both of them were
set is allowed.
Prototype

C/C++
int Hdv62_SetCallback (UINT Number, HDV62CALLBACK
Fun)
int Hdv62_GetCallback (UINT Number, HDV62CALLBACK
Fun)
 C#
int SetCallback (uint Number, HDV62CALLBACK Fun)
int GetCallback (uint Number, out HDV62CALLBACK Fun)
 VB.Net
SetCallback (ByVal Number as UInteger, ByVal Fun as
HDV62CALLBACK) As Integer
GetCallback (ByVal Number as UInteger, ByRef Fun as
HDV62CALLBACK) As Integer
Parameters
 Number
The number of device. The allowed value is from 0 to 15.
 Fun
The pointer of callback routine. Users need to declare a
callback function and set it as the parameter. The prototype
of Fun please refer to the include files. In the callback func-
tion, users can call GetImageStream routine to get pointer
of frame buffer or call GetDI routine to get the state of DI.
Return Value
No error occurs if return value >= 0; if negative value, please refer
to Section 4.9 for error information about return codes.